Valliant, Oklahoma has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 50.8 °F (low) to 74.3 °F (high). Annual precipitation averages 51.4 Inches. Valliant is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 30.8 °F | 53.7 °F | 3.25 in. |
| February | 34.5 °F | 57.9 °F | 3.63 in. |
| March | 41.6 °F | 65.6 °F | 4.51 in. |
| April | 49.0 °F | 73.3 °F | 4.74 in. |
| May | 58.7 °F | 80.8 °F | 6.2 in. |
| June | 67.6 °F | 88.9 °F | 4.17 in. |
| July | 70.6 °F | 93.3 °F | 3.61 in. |
| August | 69.4 °F | 93.8 °F | 3.33 in. |
| September | 62.8 °F | 87.4 °F | 4.18 in. |
| October | 50.8 °F | 76.6 °F | 4.74 in. |
| November | 40.8 °F | 65.0 °F | 4.26 in. |
| December | 33.1 °F | 55.6 °F | 4.75 in. |
| Annual | 50.8 °F | 74.3 °F | 51.37 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8a : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |